This invention relates generally to the manufacture of electronic equipment having etched circuit boards, and in particular to a method of mounting components having connections both on and off a circuit board.
In the manufacture of circuit board assemblies for electronic equipment, raw circuit boards are first predrilled with holes to receive component leads and then are etched and plated using conventional circuit board fabrication processes. Components, such as resistors, capacitors, sockets, etc., are then mounted equipment which not only places each component in its proper location, but crimps the leads to temporarily hold the components in place. The circuit board, with components mounted thereon, is then flow soldered, a process in which the circuit board is placed in contact with a pool of molten solder to solder each connection at once. The completed assembly is then cleaned and thereafter ready for use.
Often in manufacturing electronic equipment having circuit board assemblies, it is necessary to do a certain amount of hand wiring in the assembly process. For example, it may be necessary to connect a wire or a resistor from the circuit board to a front panel switch or potentiometer. In hand wiring, the assembler typically must test fit the wire or component, solder one end into a hole provided in the circuit board, and then solder the other end to a lug or post provided on the off-board component. After a component has been hand-soldered to the board, it sometimes must then be hand cleaned to remove flux. In densely-packed circuit boards, it is often difficult to add hand wired components without damaging nearby circuitry. Thus, it is not only time consuming to hand insert and solder components into a circuit board, but the opportunities for inadvertently damaging a completed board are numerous.
In addition to the assembly problems attendant with hand wiring, it would be desirable to eliminate the separate handling and kitting of additional parts to be added at the final assembly stage.